| Message ID | 20221117141539.406824-1-aleksandr.mikhalitsyn@canonical.com |
|---|---|
| State | New |
| Headers | show |
| Series | UBUNTU: [SAUCE] shiftfs: fix permanent -EOVERFLOW inside the CT | expand |
On Thu, Nov 17, 2022 at 03:15:39PM +0100, Alexander Mikhalitsyn wrote: > BugLink: https://bugs.launchpad.net/bugs/1990849 > > We haven't supported idmapped layers with shiftfs and moreover, that makes > no sense. Once lower fs support idmapped mounts when shiftfs is not needed. > > Starting from linux-image-5.15.0-48-generic users started seeing EOVERFLOW > errors from the userspace side on a trivial fs operations inside the containers. > > This is caused by patches ("fs: tweak fsuidgid_has_mapping()"), > ("fs: support mapped mounts of mapped filesystems"). These patches extends > and enables idmapped mounts support in Ubuntu kernel, but the problem is > that shiftfs was not properly ported. > > See also: > ("namei: prepare for idmapped mounts") > https://lore.kernel.org/all/20210121131959.646623-15-christian.brauner@ubuntu.com/ > ("overlayfs: do not mount on top of idmapped mounts") > https://lore.kernel.org/all/20210121131959.646623-29-christian.brauner@ubuntu.com/ > as a reference. > > Fixes: d347e71d2c0 ("UBUNTU: [SAUCE] shiftfs: support kernel 5.15") > Reported-by: Thomas Parrott <thomas.parrott@canonical.com> > Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> > --- > fs/shiftfs.c | 42 ++++++++++++++++++++++++++---------------- > 1 file changed, 26 insertions(+), 16 deletions(-) > > diff --git a/fs/shiftfs.c b/fs/shiftfs.c > index 76c54bc12018..9ea6e7ef06f9 100644 > --- a/fs/shiftfs.c > +++ b/fs/shiftfs.c > @@ -379,8 +379,8 @@ static int shiftfs_xattr_set(const struct xattr_handler *handler, > int flags) > { > if (!value) > - return shiftfs_removexattr(ns, dentry, name); > - return shiftfs_setxattr(ns, dentry, inode, name, value, size, flags); > + return shiftfs_removexattr(&init_user_ns, dentry, name); > + return shiftfs_setxattr(&init_user_ns, dentry, inode, name, value, size, flags); > } > > static int shiftfs_inode_test(struct inode *inode, void *data) > @@ -545,7 +545,7 @@ static int shiftfs_create(struct user_namespace *ns, > { > mode |= S_IFREG; > > - return shiftfs_create_object(ns, dir, dentry, mode, NULL, NULL, excl); > + return shiftfs_create_object(&init_user_ns, dir, dentry, mode, NULL, NULL, excl); > } > > static int shiftfs_mkdir(struct user_namespace *ns, struct inode *dir, struct dentry *dentry, > @@ -553,7 +553,7 @@ static int shiftfs_mkdir(struct user_namespace *ns, struct inode *dir, struct de > { > mode |= S_IFDIR; > > - return shiftfs_create_object(ns, dir, dentry, mode, NULL, NULL, false); > + return shiftfs_create_object(&init_user_ns, dir, dentry, mode, NULL, NULL, false); > } > > static int shiftfs_link(struct dentry *hardlink, struct inode *dir, > @@ -569,13 +569,13 @@ static int shiftfs_mknod(struct user_namespace *ns, > if (!S_ISFIFO(mode) && !S_ISSOCK(mode)) > return -EPERM; > > - return shiftfs_create_object(ns, dir, dentry, mode, NULL, NULL, false); > + return shiftfs_create_object(&init_user_ns, dir, dentry, mode, NULL, NULL, false); > } > > static int shiftfs_symlink(struct user_namespace *ns, struct inode *dir, struct dentry *dentry, > const char *symlink) > { > - return shiftfs_create_object(ns, dir, dentry, S_IFLNK, symlink, NULL, false); > + return shiftfs_create_object(&init_user_ns, dir, dentry, S_IFLNK, symlink, NULL, false); > } > > static int shiftfs_rm(struct inode *dir, struct dentry *dentry, bool rmdir) > @@ -633,10 +633,10 @@ static int shiftfs_rename(struct user_namespace *ns, > struct inode *loweri_dir_old = lowerd_dir_old->d_inode, > *loweri_dir_new = lowerd_dir_new->d_inode; > struct renamedata rd = { > - .old_mnt_userns = ns, > + .old_mnt_userns = &init_user_ns, > .old_dir = loweri_dir_old, > .old_dentry = lowerd_old, > - .new_mnt_userns = ns, > + .new_mnt_userns = &init_user_ns, > .new_dir = loweri_dir_new, > .new_dentry = lowerd_new, > }; > @@ -716,12 +716,12 @@ static int shiftfs_permission(struct user_namespace *ns, struct inode *inode, in > return -ECHILD; > } > > - err = generic_permission(ns, inode, mask); > + err = generic_permission(&init_user_ns, inode, mask); > if (err) > return err; > > oldcred = shiftfs_override_creds(inode->i_sb); > - err = inode_permission(ns, loweri, mask); > + err = inode_permission(&init_user_ns, loweri, mask); > revert_creds(oldcred); > > return err; > @@ -760,7 +760,7 @@ static int shiftfs_tmpfile(struct user_namespace *ns, > return -EOPNOTSUPP; > > oldcred = shiftfs_override_creds(dir->i_sb); > - err = loweri->i_op->tmpfile(ns, loweri, lowerd, mode); > + err = loweri->i_op->tmpfile(&init_user_ns, loweri, lowerd, mode); > revert_creds(oldcred); > > return err; > @@ -776,7 +776,7 @@ static int shiftfs_setattr(struct user_namespace *ns, struct dentry *dentry, str > struct shiftfs_super_info *sbinfo = sb->s_fs_info; > int err; > > - err = setattr_prepare(ns, dentry, attr); > + err = setattr_prepare(&init_user_ns, dentry, attr); > if (err) > return err; > > @@ -793,7 +793,7 @@ static int shiftfs_setattr(struct user_namespace *ns, struct dentry *dentry, str > > inode_lock(loweri); > oldcred = shiftfs_override_creds(dentry->d_sb); > - err = notify_change(ns, lowerd, &newattr, NULL); > + err = notify_change(&init_user_ns, lowerd, &newattr, NULL); > revert_creds(oldcred); > inode_unlock(loweri); > > @@ -973,17 +973,17 @@ shiftfs_posix_acl_xattr_set(const struct xattr_handler *handler, > return -EOPNOTSUPP; > if (handler->flags == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode)) > return value ? -EACCES : 0; > - if (!inode_owner_or_capable(ns, inode)) > + if (!inode_owner_or_capable(&init_user_ns, inode)) > return -EPERM; > > if (value) { > shift_acl_xattr_ids(inode->i_sb->s_user_ns, > loweri->i_sb->s_user_ns, > (void *)value, size); > - err = shiftfs_setxattr(ns, dentry, inode, handler->name, value, > + err = shiftfs_setxattr(&init_user_ns, dentry, inode, handler->name, value, > size, flags); > } else { > - err = shiftfs_removexattr(ns, dentry, handler->name); > + err = shiftfs_removexattr(&init_user_ns, dentry, handler->name); > } > > if (!err) > @@ -2017,6 +2017,16 @@ static int shiftfs_fill_super(struct super_block *sb, void *raw_data, > goto out_put_path; > } > > + /* > + * It makes no sense to handle idmapped layers from shiftfs. > + * And we didn't support it properly anyway. > + */ > + if (is_idmapped_mnt(path.mnt)) { > + err = -EINVAL; > + pr_err("idmapped layers are currently not supported\n"); > + goto out_put_path; > + } > + > sb->s_flags |= SB_POSIXACL; > > if (sbinfo->mark) { Adding my NAK since this was resubmitted and discussed under a new subject message id: [SRU][J/K][PATCH] UBUNTU: [SAUCE] shiftfs: fix permanent -EOVERFLOW inside the CT - corytodd
diff --git a/fs/shiftfs.c b/fs/shiftfs.c index 76c54bc12018..9ea6e7ef06f9 100644 --- a/fs/shiftfs.c +++ b/fs/shiftfs.c @@ -379,8 +379,8 @@ static int shiftfs_xattr_set(const struct xattr_handler *handler, int flags) { if (!value) - return shiftfs_removexattr(ns, dentry, name); - return shiftfs_setxattr(ns, dentry, inode, name, value, size, flags); + return shiftfs_removexattr(&init_user_ns, dentry, name); + return shiftfs_setxattr(&init_user_ns, dentry, inode, name, value, size, flags); } static int shiftfs_inode_test(struct inode *inode, void *data) @@ -545,7 +545,7 @@ static int shiftfs_create(struct user_namespace *ns, { mode |= S_IFREG; - return shiftfs_create_object(ns, dir, dentry, mode, NULL, NULL, excl); + return shiftfs_create_object(&init_user_ns, dir, dentry, mode, NULL, NULL, excl); } static int shiftfs_mkdir(struct user_namespace *ns, struct inode *dir, struct dentry *dentry, @@ -553,7 +553,7 @@ static int shiftfs_mkdir(struct user_namespace *ns, struct inode *dir, struct de { mode |= S_IFDIR; - return shiftfs_create_object(ns, dir, dentry, mode, NULL, NULL, false); + return shiftfs_create_object(&init_user_ns, dir, dentry, mode, NULL, NULL, false); } static int shiftfs_link(struct dentry *hardlink, struct inode *dir, @@ -569,13 +569,13 @@ static int shiftfs_mknod(struct user_namespace *ns, if (!S_ISFIFO(mode) && !S_ISSOCK(mode)) return -EPERM; - return shiftfs_create_object(ns, dir, dentry, mode, NULL, NULL, false); + return shiftfs_create_object(&init_user_ns, dir, dentry, mode, NULL, NULL, false); } static int shiftfs_symlink(struct user_namespace *ns, struct inode *dir, struct dentry *dentry, const char *symlink) { - return shiftfs_create_object(ns, dir, dentry, S_IFLNK, symlink, NULL, false); + return shiftfs_create_object(&init_user_ns, dir, dentry, S_IFLNK, symlink, NULL, false); } static int shiftfs_rm(struct inode *dir, struct dentry *dentry, bool rmdir) @@ -633,10 +633,10 @@ static int shiftfs_rename(struct user_namespace *ns, struct inode *loweri_dir_old = lowerd_dir_old->d_inode, *loweri_dir_new = lowerd_dir_new->d_inode; struct renamedata rd = { - .old_mnt_userns = ns, + .old_mnt_userns = &init_user_ns, .old_dir = loweri_dir_old, .old_dentry = lowerd_old, - .new_mnt_userns = ns, + .new_mnt_userns = &init_user_ns, .new_dir = loweri_dir_new, .new_dentry = lowerd_new, }; @@ -716,12 +716,12 @@ static int shiftfs_permission(struct user_namespace *ns, struct inode *inode, in return -ECHILD; } - err = generic_permission(ns, inode, mask); + err = generic_permission(&init_user_ns, inode, mask); if (err) return err; oldcred = shiftfs_override_creds(inode->i_sb); - err = inode_permission(ns, loweri, mask); + err = inode_permission(&init_user_ns, loweri, mask); revert_creds(oldcred); return err; @@ -760,7 +760,7 @@ static int shiftfs_tmpfile(struct user_namespace *ns, return -EOPNOTSUPP; oldcred = shiftfs_override_creds(dir->i_sb); - err = loweri->i_op->tmpfile(ns, loweri, lowerd, mode); + err = loweri->i_op->tmpfile(&init_user_ns, loweri, lowerd, mode); revert_creds(oldcred); return err; @@ -776,7 +776,7 @@ static int shiftfs_setattr(struct user_namespace *ns, struct dentry *dentry, str struct shiftfs_super_info *sbinfo = sb->s_fs_info; int err; - err = setattr_prepare(ns, dentry, attr); + err = setattr_prepare(&init_user_ns, dentry, attr); if (err) return err; @@ -793,7 +793,7 @@ static int shiftfs_setattr(struct user_namespace *ns, struct dentry *dentry, str inode_lock(loweri); oldcred = shiftfs_override_creds(dentry->d_sb); - err = notify_change(ns, lowerd, &newattr, NULL); + err = notify_change(&init_user_ns, lowerd, &newattr, NULL); revert_creds(oldcred); inode_unlock(loweri); @@ -973,17 +973,17 @@ shiftfs_posix_acl_xattr_set(const struct xattr_handler *handler, return -EOPNOTSUPP; if (handler->flags == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode)) return value ? -EACCES : 0; - if (!inode_owner_or_capable(ns, inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; if (value) { shift_acl_xattr_ids(inode->i_sb->s_user_ns, loweri->i_sb->s_user_ns, (void *)value, size); - err = shiftfs_setxattr(ns, dentry, inode, handler->name, value, + err = shiftfs_setxattr(&init_user_ns, dentry, inode, handler->name, value, size, flags); } else { - err = shiftfs_removexattr(ns, dentry, handler->name); + err = shiftfs_removexattr(&init_user_ns, dentry, handler->name); } if (!err) @@ -2017,6 +2017,16 @@ static int shiftfs_fill_super(struct super_block *sb, void *raw_data, goto out_put_path; } + /* + * It makes no sense to handle idmapped layers from shiftfs. + * And we didn't support it properly anyway. + */ + if (is_idmapped_mnt(path.mnt)) { + err = -EINVAL; + pr_err("idmapped layers are currently not supported\n"); + goto out_put_path; + } + sb->s_flags |= SB_POSIXACL; if (sbinfo->mark) {
BugLink: https://bugs.launchpad.net/bugs/1990849 We haven't supported idmapped layers with shiftfs and moreover, that makes no sense. Once lower fs support idmapped mounts when shiftfs is not needed. Starting from linux-image-5.15.0-48-generic users started seeing EOVERFLOW errors from the userspace side on a trivial fs operations inside the containers. This is caused by patches ("fs: tweak fsuidgid_has_mapping()"), ("fs: support mapped mounts of mapped filesystems"). These patches extends and enables idmapped mounts support in Ubuntu kernel, but the problem is that shiftfs was not properly ported. See also: ("namei: prepare for idmapped mounts") https://lore.kernel.org/all/20210121131959.646623-15-christian.brauner@ubuntu.com/ ("overlayfs: do not mount on top of idmapped mounts") https://lore.kernel.org/all/20210121131959.646623-29-christian.brauner@ubuntu.com/ as a reference. Fixes: d347e71d2c0 ("UBUNTU: [SAUCE] shiftfs: support kernel 5.15") Reported-by: Thomas Parrott <thomas.parrott@canonical.com> Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> --- fs/shiftfs.c | 42 ++++++++++++++++++++++++++---------------- 1 file changed, 26 insertions(+), 16 deletions(-)